JPS60235704A - Preproduction of tetrahydroanthraquinones in supply solutionto be added into hydrogen peroxide working solution - Google Patents

Abstract

The invention provides a process to increase the mol ratio of nuclearly hydrogenated working compound to the total working compound in a make-up solution to be added to the working solution of an operating plant in producing hydrogen peroxide by the cyclic reduction, oxidation, and extraction of an alkylated anthraquinone. The process produces the nuclearly hydrogenated working compound in the make-up solution without producing substantial quantities of undesired by-products.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for hydrogenating 2-alkylanthraquinones to produce 5,6,7,8-tetrahydrohydrochloride in a working solution without concomitantly producing substantial amounts of undesirable by-products. This invention relates to an economical method for producing derivatives and to a method for producing hydrogen peroxide using said working solution.

No. 2,158,525 to Riedl et al. teaches that upon oxidation, polynuclear organic hydroquinones can produce hydrogen peroxide and the corresponding quinones.

Currently, almost all commercially available hydrogen peroxide is produced by the anthraquinone process, which involves cyclically adding hydrogen to a solution containing a 2-alkylanthraquinone. to produce the corresponding 2-anthuhydroquinone, and the latter is converted into fH to produce 2-alkylanthraquinone and hydrogen peroxide. [Working compound J (worktng c, om-pound 8
It is called 1. Working compounds considered to be currently in commercial use include 2-ethyl anthraquinone, 2-1-butylanthraquinone, 2-amyl anthraquinone (usually mixed secondary and octamyl compounds) and the like. It is a derivative of During the hydrogenation step, some of the anthraquinone is nuclearly hydrogenated to form the 5.6.7.8-tetrahydroenzyme derivative (commonly abbreviated as "tetrahydro" or "tetra"); Conductors can also generate hydrogen peroxide and are considered working compounds.

Many other by-products are also produced in the working solution; stiff by-products are undesirable because they do not contribute to the production of hydrogen peroxide.

Therefore, the presence of such by-products is undesirable. This is because they result in the loss of expensive working compounds and furthermore, contacting the working compounds with compounds such as activated alumina increases C
This is because it is necessary to purify the working compound by replacing some of these by-products with the working compound. However, such processing
1, resulting in a total loss of expensive working compounds and expensive solvents.

Additionally, thousands of undesirable hook organisms are extracted into the aqueous hydrogen peroxide, increasing the dissolved carbon content of the hydrogen peroxide, or even producing undesirable colors or odors in the hydrogen peroxide.

The operating conditions of the Ansquinone Hydrogen Peroxide Plant are related to the amount of filtered hydrogen oxide produced per cycle and the time required to complete said cycle. The presence of tetrahydro working compounds in the working solution is one of the important factors to be considered in establishing optimal operating conditions for the plant.

US Pat. No. 8,078,680 to Zieny et al. teaches that it is desirable for at least 85316 of the working compound to be in the tetrahydro form and is incorporated herein by reference. Furthermore, the patent of Zienyi et al. discloses that 2-ethyl-5,6-2-ethyl-5,6-
, 7,8-tetrahydroanthraquinone.

The working solution described in the reference patent initially has a working compound of 8.4.9/A, of which 64 are 2-ethyl anthraquinone, and 36316 is 2-ethyl anthraquinone.
5,61718-tet'yhydro7thraquinone. However, after addition of hydrogen fJj for %7 hours, Φ,'lj
The working compound of J/i was used as a seedling, all of which were in the tetrahydro-11 state, and the original working compound was added to (7) at a weight of about 40 light.

US% Grant to Dorsey et al. No. 2. No. 95,229 teaches a method for producing tetrahydroanthrahydroquinone with a yield of about 85X glass apparatus width. Shikaru,
Dorsey et al.'s method requires a special porous nickel catalyst that is not suitable for use with boric acid cable widths.

British Patent No. 1,390.408 teaches a process for the preparation of hydrogen peroxide using a working solution containing 2-8-amyltetrahydroanthraquinone and 2-2-isoamyltetrahydroanthraquinone. The tetrahydroanthraquinones are disclosed in U.S. Pat. No. 2,495,229 using porous nickel catalysts at atmospheric pressure and elevated temperatures.
It is first manufactured by the method of No. British patent 1,890
．． The method of No. 408 is to convert tetrahydroanthraquinone 7 to I
It has the disadvantage of requiring a prehydrogenation step for R production. This tetrahydroanthraquinone 7 is then isolated and a second, different hydrogenation step is required to produce 2-amyltetrahydroanthrahydroquinone in the working solution. It is economically desirable to synthesize the tetrahydroanthrahydroquinone in the solvent to be used in the working solution.

During the operation, it is necessary to add or supplement the working solution with both the solvent and the working compound in order to compensate for losses.

Typically, the supplementary working compound is added as the anthraquinone rather than in the tetrahydrolot form of the working compound or as a mixture of anthraquinone and its tetrahydro derivative.

The tetrahydro component of the working compound increases gradually with use. However, during this time other by-products are formed which attenuate the working compounds in the working solution.

Thus, even when a relatively small proportion of the anthraquinone form of the make-up work compound is added to the work melt, undesirable by-products are formed as a result of the relatively harsh hydrogenation conditions.

Besides, the productivity of the plant is suppressed during the production of the tetrahydro component in the working solution. This decrease in productivity results in significant economic loss.

without producing substantial - undesirable by-products.
and without reducing the productivity of the catalyst or working solution of the operating plant. 1. It would be desirable to develop a rapid method of increasing the ratio of the tetrahydro component of the working compound to the total working compound that must be added to the solution.

This objective is achieved by the method of the invention. The method of the invention prepares a first solution containing a non-nuclearly hydrogenated alkylanthraquinone in an inert solvent, and the concentration of the working compound non-nuclearly hydrogenated anthraquinone corresponds to that produced during the subsequent hydrogenation step. The concentration of the solution is adjusted so that the concentration of anthrahydroquinone is below the saturation concentration of anthrahydroquinone. This first solution is then hydrogenated at below 50° C. in the presence of a palladium catalyst, thereby reducing the ratio of tt1\working compounds to total working compounds without the actual formation of undesirable by-products. increase and then add nli light and (-) to the flant working solution.

The working compound is any 2-
The 2-alkylanthraquinone working compound, which may be based on an alkyl-7 nothraquinone, is selected from the group consisting of 2-ethylanthudiquinone, 2-butylanthraquinone, as well as 2-amylanthraquinone. This is desirable.

The working compound can be dissolved in any inert solvent to form the first solution. The inert solvent used is a component of the working solution to be used for hydrogen peroxide production, so that the solution of the working compound produced according to the invention is peroxidized by cyclic hydrogenation and oxidation of the alkylated anthraginone. It is preferred that it is suitable for direct addition to the process silica stream of a plant producing hydrogen. The solvent may be a novel solvent or a recycled solvent.
For example, it is well known that substantial amounts of solvent can be evaporated from the working solution in an oxidizer and recovered from the overflow air or Fi-oxygen by condensation or sorption. Alternatively, if it is desired only to increase the concentration of the working compound in the working solution without the addition of a solvent, the solvent used is
Optionally, after the purification step, additional working compounds may be present in at least a portion of the plant working solution, to which additional working compounds are simply added to form the first solution.

It is well known that in the production of hydrogen oxide, palladium catalysts are preferred over nickel catalysts for the hydrogenation of the anthrahydroquinone form of the working compound, since the possibility of causing nuclear hydrogenation is small. . However, it was surprising to find that palladium catalysts were found to be suitable for catalyzing the hydrogenation of the non-nuclear hydrogenation form of the working compound to the tetrahydro form of the working compound, and The form is '#1m
It is critical to the economy of the invention that it is not necessary to use a first catalyst for the reduction of the quinone form of the working compound and a second catalyst for the reduction of the quinone form of the working compound to the hydrogenated form.

The hydrogenation process of the present invention is capable of neutral plant hydrogenator operation under the critical conditions claimed herein. However, if there is no excess hydrogenation capacity, it is more economical to avoid reducing the production capacity of the plant and instead hydrogenate the make-up working solution in a separate hydrogenator.

Often, an operational hydrogen peroxide plant may utilize a sidestream hydrogenator or a plant unit with one pilot-scale hydrogenator to accommodate the catalyst, solvent, and working compounds; A hydrogenator or pilot unit hydrogenator may serve well in the practice of the present invention.

The hydrogenator can be operated with 100% recirculation of the working solution until the desired ratio of tetrahydro working compound to total working compound is reached, but the replenishment solution in the pilot scale hydrogenator is prepared. At times, it is also possible that only a portion of the working solution passes through the oxidizer and extractor circulation. For reasons of completeness and economy of implementing the invention in a pilot unit, it may not be desirable to pass the hydrogenated solution through the remainder of the pilot unit without an oxidizer and extractor in operation. By maintaining at least 90% recirculation of the solution through the hydrogenator, the depth of hydrogenation is increased to enable substantial production of tetrahydro working compound within the hydrogenator. at the same time,
The remaining 10'56 or less of the working solution can be oxidized, the hydrogen peroxide extracted, and the working solution recycled back to the hydrogenator, thereby flushing the rest of the plant with inert gas as a safety precaution. There is no need to cover the

When carrying out the present invention in the sidestream hydrogenator, up to 1096 of the first solution from the sidestream hydrogenator is added to the plant working solution and at least 9096 of the first solution is recycled to the sidestream hydrogenator. igniting the concentration of the working compound in the working solution in stages by circulating and simultaneously replacing a portion of the first solution with additional solvent and working compound that is added to the working solution as a replenishing solution. There are some things that are desirable.

At least 90 days of hydrogenated working solution, preferably negative e
It is critical to the process that the Nutrium 9596 is recycled to the hydrogenator until the desired ratio is reached to minimize the production of undesirable by-products. It is not conclusive whether the hydrogenator is a fixed bed hydrogenator or a fluidized bed hydrogenator.

It is undesirable to keep the hydrogenator below about 50℃.
Preventing the substantial formation of 1/+ products is also critical to the practice of the present invention. Although temperatures below 40° C. are not without concern regarding the formation of undesirable by-products, it is clear that such relatively low temperatures reduce both the rate of hydrogenation and the solubility of the working compounds. Therefore, preferred operation @ degrees L is below about 40<0>C to 50<0>C.

The pressure of hydrogen gas in the hydrogenator is about 50 to about 400 k
It is inconclusive over the range of Pα. Those skilled in the art will recognize that increasing the pressure increases the rate of hydrogenation. However, within the above range, pressure has little effect on the formation of undesirable impurities. Preferably, the hydrogen pressure is in the range 100-200 kPa to minimize safety hazards and optimize equipment cost.

Additional non-nuclear hydrogenation working compound can be added to the solution undergoing hydrogenation to increase the concentration of working compound to a desired or design level. Additional working compound may be added in one or more increments as long as the total concentration of non-nuclear hydrogenation working compound does not exceed the saturation concentration of the hydroquinone form in the hydrogenator.

The following examples will illustrate the best mode of the claimed invention to those skilled in the art.

Example A hydrogenation plant was designed to allow control of solution flow rate, liquid temperature, pressure, and gas flow rate.

The palladium catalyst disclosed in US Pat. No. 8,635,841 was used in a fixed bed configuration to eliminate catalyst attrition and to eliminate filtration problems. Equipped with a suitable sampling boat.

The quinone form of the working compound was dissolved in a suitable solvent and the air in the thread was replaced with nitrogen. When the desired temperature was reached, the nitrogen was removed and hydrogenation was allowed to proceed by adjusting the flow rate of the quinone solution and the gas replacement at a predetermined pressure with hydrogen supplied to the C yarn. Periodically, a sample is removed from the reservoir through the sampling valve and filter, oxidized and
% II, extracted with SO4 (7, and analyzed by gas chromatography to reveal 2-alkyl-5,6,7,
The content of 8-tetrahydroanthraquinone and its parent quinone was determined.

Comparative example mixed solvent, 67% diisobutyl carbinol IDIB
A working bath solution consisting of 25 wt.
14! ! ! Shita. U.S. Patent No. 3,685 for the hydrogenator.
The catalyst 824y disclosed in No. 841 was charged, and 50
It was operated at a hydrogenator inlet temperature of 0.degree. C. to remove inherent poisons from the working solution. A rapid drop in titer (from 78 to 513) was observed during the first two days of operation. The catalyst bed was replaced with a new catalyst 824y and the operation was restarted. A similar decrease in titer was again observed. Heating the catalyst bed under an elevated wedge of N did not change the force to 1+lb. After 24 hours of operation, the catalyst was replaced with fresh catalyst 584y, and at the end of 0453 days when operation was restarted, an additional charge of fresh catalyst ill was made to bring the total catalyst type-1 to 650y. Operation was resumed at a hydrogenator population temperature of approximately 45°C. A rapid drop in titer from 17B to 118 was observed. The catalyst bed was then heated to about 100° C. under nitrogen purge through the bed to remove water from the catalyst bed. In this regard, the working solution was assumed to be non-toxic and suitable for use in order to obtain meaningful data. Continuous operation was started at a hydrogenator inlet temperature of 45°C. The titer was 12 in about 40 hours.
A decrease from 6 to 106 was observed. The catalyst bed was regenerated with nitrogen for 2 hours and the operation restarted.

During 52 hours of operation, the titer gradually dropped from 128 to 101. This repeated drop in titer was attributed to impurities polluting the catalyst bed. The operation was interrupted and the catalyst bed was washed with a mixed solvent in an attempt to remove suspected impurities from the catalyst bed. Following cleaning of the catalyst bed, continuous operation was resumed at a hydrogenator inlet temperature of 45° C. and the downward trend continued for the next 70 hours of continuous operation.

Example 1. 6X solution of 2-ethyl anthdiquinone in a solvent containing 27X trioctyl phosphate and 78% S3 solvent system 1
．． 600? A hydrogenation pilot was operated with a solution containing . After thoroughly exchanging the yarn with nitrogen, hydrogenation was carried out for 4 hours.
Hydrogen odor treatment at 5°C and <75 kPa was started.

8.5, (+, 7,
The concentration of B-tetrahydro-2-ethyl anthraquinone was determined to be 4% by weight, at which point additional 2-ethyl-anthraquinone was added to raise the total working compound level to 996%. After a further 8 hours of hydrogenation, a concentration t'm of 6.25X of the tetrahydro conductor was reached.

No desired by-products were observed.

Example 2 Same conditions as Example 1, but C, aliphatic alcohol-S
The apparatus of Example 1 was operated with a 159 solution of 2-amine anthraquinone in a solvent mixture. After 11 hours, the concentration of the tetrahydro derivative had increased to h 46 'A.

Additional 2-amyl anthraquinone was added to increase the solids concentration by 203 Jov-. Hydrogenation was continued for a further 16 hours, at which point the tetrahydro working compound IH,AA
The concentration of QI was 8.2%.

Additional 2~amyl anthraquinone was added to give a solids concentration of 25% and after a further 19 hours of hydrogenation, the tetrahydro working compound level was U12.16. Under the mild conditions used, no undesirable by-product formation was detected.

Example 8° Catalyst 210y and 16316 in DIBC-S vine solvent system
Example 18 was repeated using 15 liters of AAQ solution.

The hydrogenation inlet temperature ranges from 40°C and the pressure
It was in the range of 75kPa-410kPa. At regular time intervals a portion of the reaction mixture was analyzed by gas chromatography. The production rate of the 5,6,7.8-tetrahydro working compound (H4AAQr) is shown in Figure 1. Liquid chromatography analysis of the final product showed no other quinone-related by-products and Example 4 Plant Start-up H4A A Q was also produced in a conventional plant using 90-95 recycle to a fixed-bed hydrogenator to promote 78
X 2-amyl anthraquinone (consisting of 22 liters of AAQI, concentrated in a DIEC-S vine mixed solvent. This solution was hydrogenated in a process blunt over a 115 cm fixed bed catalyst), oxidized, and then subjected to extraction under 6 liters of pilot conditions. Hydrogenation inlet temperature 40-45°C Hydrogenator inlet pressure 375-410 kPaOxidation degree temperature 40-42°C Oxidizer pressure 210-15kPa Extractor temperature 25-80°C Gold mud to hydrogenator (with recirculation) The production rates of H,AAQ, including 1 600 m/min recycle flow to the hydrogenator 540 t//min flow to the fermenter 60 d/min are shown in Table 2. Gas and liquid chromatography analyzes No kinin-printed organisms were shown.

Example 5 Example 1 was repeated using solution #5 containing an EAQ of about 4.59 and operated at 40°C and 375 kPa.

The results are shown in Table 8.

Example Using a catalyst of 6°zooy, about 1% in DIBC-S vine solvent
Example 5 was repeated with one small aliquot of the solution containing 5316 AAQ.

The results are shown in Table 4.

Table 1 (Example 8) 0 16.0 '0.0 21.2 48.0 6 4.5 85.8 10, 6.7 1ih i lJ, 5 Z 0 14.1 22 15.0 24115.7 26 15.8 Table 2c Example 4) Time (hour I AAQ% H, AAQ96U l 5.U
O, (1 8B, 0 24 8・8 32 4.8 52 7・4 56 7.8 60 6.7 8.2 Hours (hour I EAQ% H4F A Q560 4.5
,4. C30,t) 5 B, 19 1.15 8 Z, C11,79 121,992,44 16'1.41 2.91 Table 4 (Example 6) Production rate time of tetrahydro compound (hour I A A Q96 H4A A Q91.1
146, 1446 tJ, 04112・81.8 11 9.7 4.6 Procedural amendment (method) % formula % 1 Display of case 1985 Patent Application No. 74594 2 Name of invention Added to hydrogen peroxide working solution Relationship with the case of a person making pre-production 3 corrections for tetrahydroanthraquinones in a replenishment solution Patent applicant name FMC Co-Boration 4 Agent 07 Address Akasaka 1-1-18 Akasaka, Minato-ku, Tokyo Taisei Building (
Phone 582-71611s? As shown in the engraving of the handwritten specification attached to the original subject application 6, contents of amendments, there are no amendments to the contents.

Claims (1)

[Scope of Claims] (1) A method for producing hydrogen peroxide through a cyclic process of reducing, oxidizing, and extracting a working solution containing alkylated anthraquinone and the corresponding hydroquinone, tetrahydroanthraquinone, and tetrahydroanthrahydroquinone as working compounds. adjusting the concentration of the non-nuclear hydrogenated working compound below the maximum solubility of the alkylated anthrahydroquinone formed in the first solution at the hydrogenation temperature;
The first solution is hydrogenated in the presence of a palladium catalyst at a pressure of 50 to 400 kilopascals and a temperature below 50° C. to thereby remove the tetrahydro component of the working compound without the formation of substantial amounts of undesired by-products. A method for producing hydrogen peroxide, characterized in that the molar ratio of the nuclear hydrogenated tetrahydro component of the working compound in the first solution to be added to the working solution is increased by increasing the ratio. 2 Alkylated anthraquinone is 2-ethylanthraquinone, 2-isobutylanthraquinone, Vc, 2
- amyl anthraquinone, the pressure is from 100 to 200 kilopascals, and the hydrogenation temperature is from 40°C to 50°C, and the hydrogenation temperature ranges from 40°C to 50°C. 8. The method of claim 1, wherein at least 90% of the hydrogenated first solution is recycled to the hydrogenator. 4. the alkylated anthraquinone is selected from the group consisting of 2-ethyl anthraquinone, 2-inbutyl anthraquinone, and 2-methyl anthraquinone, and the pressure is
9. The method according to claim 8, wherein the hydrogenation temperature is 100 to 200 kPa and the hydrogenation temperature is 40 to 50C. 50 2-ethyl anthraquinone as working compound, 21
Tubutyl anthraquinone, 2-amyl anthraquinone,
the corresponding 2-alkylanthrahydroquinone, the corresponding 5°6.7.8-tetrahydro-2-alkylanthraquinone and the corresponding 5,6,7.8-tetrahydro-2
- A process for the production of hydrogen peroxide by a cyclic process of reducing, oxidizing and extracting a working solution containing one or more compounds selected from the group consisting of alkylanthrahydroquinones, the process comprising non-nuclear hydrogenation. The concentration of the compound is adjusted to the maximum solubility of the alkylated anthrahydroquinone formed during the formation in the first solution at the hydrogenation temperature,
hydrogenating the first solution at a pressure of ~400 kPa and a temperature of 40 °C to 50 °C, recycling at least 9 (1%) of the working solution to the hydrogenator without oxidation and extraction;
adding the first solution as a supplement to the working solution by thereby increasing the molar ratio of the tetrahydro component of the working compound without producing substantial amounts of undesirable by-products, and adding the first solution to the working solution as a supplement. A method for producing hydrogen peroxide, characterized in that the molar ratio of the nuclear hydrogenated tetrahydro component in the first solution to be produced is increased. 6. The method of claim 5, wherein the first solution comprises a working solution removed from the flint processing stream. 7. The method of claim 5, wherein the conditioning step is repeated at least once after the hydrogenation step. 8. As a working compound, 2-ethyl anthraquinone, 2
-isobutylanthraquinone, 2-amyl anthraquinone, corresponding 2-alkylanthraquinone, corresponding 5
, 6°7.8-tetrahydro-2-alkylanthdiquinone and CJ' corresponding 5,6.7.8-tetrahydro-
A process for the production of hydrogen peroxide by a cyclic process of reducing, oxidizing and extracting a working solution containing one or more compounds selected from the group consisting of 2-alkylanthrahydroquinones in a side stream hydrogenator. hydrogenating a first solution containing a working compound and an inert solvent at a pressure of 400 kilopascals and a temperature below 50°C;
Nuclear hydrogenation increases the molar ratio of the tetrahydro component in the first solution by adding up to IO9 of the first solution from the side stream hydrogenator as a supplement to the working solution, without oxidation and extraction. recycling at least a portion of the first solution as replenishment to the flow hydrogenator, thereby further increasing the molar ratio of the tetrahydro component of the working compound without producing substantial amounts of undesired by-products; The concentration of the non-nuclear hydrogenated working compound is adjusted below the maximum solubility of the alkylated anthudiquinone formed in the first solution at the hydrogenation temperature, and at the same time a portion of the first solution is added as a make-up to the working solution. , a process for producing hydrogen peroxide, which comprises substitution with additional solvent and working compounds. 9. The method of claim 8, wherein the additional solvent comprises a working solution removed from the plant process stream. 9. The method of claim 8, wherein the process of clause v4 is repeated at least once after the deuterium addition step.